Drafting table



Patented Dot. 26, 1948 UNITED STATES PATENT oFFicE Gordon W. Yarbeigseattle, Wash. A Application February 25. 1946, Serial Nora-9,958

drafting tables and tables of other kinds wherein the tabletop is pivotally or hingedly mounted to permit its-being angularly adjusted or tilted to different positions; it being the principal object of the invention to provide a simplified and effective means for use in such tables for holding the table topat any set position of adjustment, and which may be easily manually actuated to release the table top for adjustment and will be automatically restored to holding position.

Furthermore, it is an object of this invention to provide a novel spring actuated clamping means normally holding the table top at a set position of adjustment, and manually actuated means for relieving the clamping pressure to permit change in adjustment.

More specifically stated, it is the object of this invention to provide an improved clamping means fol-holding a pivotally supported table top at any set position of adjustment, comprising spring 4 Claims. (01. 311-38),

pressed clamp bolts mounted in the top supporting structure and engaging certain parts of the table top' for holding the adjustment, and novel arrangement of toggle levers operable by foot pedal mechanism to simultaneously effect the movements of the clamping bolts for the release of their holding pressure.

' Still further objects of the invention reside in the details of construction of parts embodied in the invention and in their combination and mode of use as will hereinafter be fully described.

In accomplishing these and other objects of the invention, I have provided the improved details of construction, the preferred forms of which are illustrated in the accompanying drawings,

I designates the top portion of a drafting table ,embodyingthe present invention. This top is supported by a base frame structure comprising opposite end standards 2 and 2? that are joined inlispaoed, upright position by a lower cross rail 3 and an upper cross rail 5. Suitable diagonal bracing members 6 are extended from the central portion of the lower rail to the outer end por- 5 tions of the cross rail 5.

As noted best in Figs. 1 and 3, each of the arrangement of parts at the opposite 2 p standards 2 and 2' comprises spaced apart sections," designated at M and 2b in Fig. 3, forming the inner and outer faces of the standards, and fixed solidly between these spaced sections of each standard and at the lower ends thereof, are brackets 8 and 8 that extend horizontally-to sufiicient distance in a forward direction to give adequate support for the table against forward or-rearward tilting. In this description-, the side at which the draftsman stands is consideredto be the forward side or front of the table.

-As noted in Fig. 2, the standards 2 and .2 are somewhat forwardly inclined from lowerto' upper ends in order to bring the center of gravityof the top I as supported thereby substantially centrally over the base structure. l Fixed to the table top, near its opposite ends and on its under side, are supporting rails or'flange's Hi and it), set in parallel, vertical planes, and each disposed between the spaced inner and outer sections 2a and 2b of the standard at the corre sponding end of the supporting structure.v Pivot bolts l2 extend through the upper end portions of the standards and through the flanges to thereby pivotally mount the table top fortilting adjustment.

Formed in each of the flanges In and Ill, in arcs of the same radius and about theircorrespending-pivot bolts l2 as centers, are slots I5, as noted in Fig. 2, and extended through each of these slots and through the adjacent member of the supporting structure, is a clamp bolt 16, as shown best in Fig. 3. v i

It will be understood by reference to the detailed showing in Fig. 3, that each bolt 16" is slidably contained in a sleeve or tube 20 that-is fixedly mounted inthe insidesection 2a of the supporting standard at that side of the table. On the outer end of each bolt [6 is a washer 2! held by a nut- 22. At its inner end, each' bolt extends substantially beyond the'inner end'of its mounting-sleeve and is formed with a head IE and between the head of the bolt and adjacent end of the sleeve, is a coiled spring 25 held under compression thereby to urge the bolt inwardly and, byreason of the washer and nut at its'oute'r end, to effect the tight clamping-of the flange against the inner section of the standard and thus mm the table top against'movement on its'pivotbolts l2.

As noted in Fig. 3, a hole 2B-is provided in the outer section of the standard 'to give access with 'ampleclearance, to the'nut 22 and washer" 21". It 'is to be understood, also, that the details and end o'f'the table are like those shown in' Fig.3. 7

To provide for a quick and easy release of the lever.

clamping action of the bolts It at opposite ends of the table, I have provided a releasing mechanism which will now be described.

It is observed by reference to Figs. 1 and 3 that the cross rail is secured at its opposite ends to blocks 30 which, in turn, are fixed to the inside section of the adjacent standard. Also, web plates as at 1232 are applied to, opposite sides of the rail 5 at'its ends and to the blocks 30 to add rigidity to the structure. These spaced webs at each end of the cross rail 5 provide guideways between them for containing therein the opposite end portions of a toggle linkage whereby the clamp bolts may be simultaneously released. This toggle linkage, as seen in Fig. 1, comprises two levers 35 and 35', disposed above and in the plane of the rail 5, with their inner ends pivotally engaged one with the other and their outer ends contained, respectively, in the guideways formed between the webs 32 at opposite ends of rail 5.

. Atits outer end, each lever has a screw bolt 40 adjustably mounted thereinand the heads of these bolts engage against the heads of the corresponding bolts 16, as shown in Fig. 3.

As noted in Fig. 4, the lever 35 has a rounded end surface and the end of lever35' has a socket to receive it pivotally, and the levers are of such length that normally they are upwardly inclined from their outer toward their engaged ends, as shown infull lines in Fig. 1. Guide flanges 45 are fixed to the crossrail 5, at opposite sides and spaced from its-ends to hold the toggle levers in proper place, I

Pivoted to the lower cross rail 4 at about its I medial point, by a pivot 49, is a foot lever 50. This lever extends in a forward direction to a suitable distance, as shown in Fig. 2, and connected therewith, forward of the pivot 49, is the lower end of a pull rod 52 which extends upwardly therefrom through a hole 53 in the cross rail5 and is fastened to the lever 35 near its inner, end. Preferably the rod extends through a 4 claim as new therein and desire to secure by Letters Patent is:

l. A table of the character described com prising a supporting frame structure including spaced standards, a table top having supporting ribs fixed thereto at opposite ends and pivotally mounted by said standards for tilting adjustment of the said top, clamp bolts movably mounted in the standards at opposite ends of the frame structure to engage with said supporting ribs of the table top, springs acting on the bolts to normally retain them in clamping contact with the vertical hole in the lever and is secured by a nut 55 at its upper end that engages against the Withthe parts tr theztable so arranged, it will" be understood that normally the coiled springs 25, acting on the clamp bolts, Iii-I6,

plished by depression of the foot pedal, or lever 50, which, by reason of pull rod 52, will pull the toggle linkage downwardly, toward straightened position, thereby extending its length and causing the bolts IE to be pushed outwardly against the spring pressure, thereby releasing their holding effect on the flanges Ill and i0, and permitting the' table top to be adjusted on its pivot bolts l2 to the desiredposition. Then, upon release of downward pressure on the foot pedal, the coiled springs 25,actuate the bolts back into clamping contact with the supporting flanges illl0 of the table top to hold the adjustment. It will be, understood that there may be changes made in table design, especially in supporting structure, without departing from the spirit of the invention, and therefore it is not desired that claims be limited to details, but that they be given an interpretation that is commensurate with the scope of the invention disclosed.

Having thus described my invention, what I ribs to retain an adjustment of the table top, and a toggle linkage extended between the bolts and operable to simultaneously move them against the spring pressure to release their clamping action for adjustment of the top.

2. A table of the character described comprising a supporting frame structure including spaced standards, a table top having supporting ribs fixed thereto at opposite ends, and pivotally mounted by said standards for tilting adjustment of the top, and having arcuate slots therein concentric of their pivotal mountings, clamp bolts mounted for endwise movement in the standards and extended through said .arcuate slots and having clamping heads on their outer ends to engage the ribs, springs acting on the bolts to normally retain their heads in clamping contact with the ribs, a toggle linkage extended between the bolts and engaged with their inner ends and a foot lever operable to actuate the linkage to simultaneously shift the bolts outwardly to release their clamping action for adjustment of the table top.

3. A table of the character described comprising a supporting frame structure including spaced standards and cross bars joining the standards, a table top having supporting ribs fixed thereto at opposite ends and pivotally mounted by said standards for tilting adjustment of the top, and having arcuate slots therein concentric of the pivots, clamp bolts mounted for endwise movement in the standards and extended through said arcuate slots and having clamping heads at their outer ends engaging said ribs, springs mounted on the inner ends of the bolts and acting thereon to normally retain their heads in clamping contact with the ribs, a toggle linkage supported by one of the cross bars and engaged at its ends with the inner ends of the bolts, a foot pedal pivoted in the frame and means connecting the pedal and toggle linkage for its actuation to simultaneously release the clamping action of the bolts.

4. A table as recited in claim 3 wherein the bolts are contained in sleeves fixed in the standards, and said bolts extend beyond the inner ends of said sleeves and mount the coiled springs thereon.

I GORDON W. YARBER.

REFERENCES orran The following references are of record in the file of this patent:

UNITED STATES PATENTS 'DeLisle July 30, 

